A web director per se is known to those skilled in the art of paperboard corrugators. Such web directors are provided immediately upstream of the cut-off machine. For representative samples of such prior art web directors, see U.S. Pat. Nos. 4,194,662 and 3,307,441.
It is believed that all prior web directors have straight surfaces for changing the elevation of a web. In actual practice, there is a limit to the angle of the web support with respect to the horizontal, beyond which the web will break. Thus, the aforementioned angle should generally not be more than about six degrees. U.S. Pat. No. 4,328,727 states that the angle should not be more than 7.degree.. This limitation determines the length of floor space needed for the web director. As the difference in elevation for movement of the web increases, the length of the web director must also increase so that said angle is not more than about 6.degree.. The solution for minimizing floor space set forth in the last mentioned patent is substantially different from that set forth hereinafter.
The present invention is directed to solution of the problem of how to decrease the length of the web director without breaking the web of paperboard and thereby reducing the length of corrugator floor space needed for the web director.